Critical severity10.0CISA KEVNVD Advisory· Published Aug 6, 2026· Updated Sep 25, 2026
CVE-2026-5430
CVE-2026-5430
Description
The JWT authentication mechanism accepts tokens signed with algorithms other than those explicitly configured or supported. This allows an attacker to craft a JWT with an unsupported algorithm, which is then incorrectly validated, leading to unauthorized access.
Successful exploitation of this vulnerability may result in unauthorized access to the system, including the potential compromise of administrative accounts and full account takeover. The CVSS score is adjusted to 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) in single-tenant deployments, reflecting that the impact is contained within a single security authority boundary.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Patches
Vulnerability mechanics
References
2- security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5328/nvdVendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalognvdUS Government Resource
News mentions
6- CISA Warns of WSO2 Multiple Products Vulnerability Exploited in AttacksCyber Security News · Sep 25, 2026
- WSO2 and Adobe Commerce Flaws Exploited in Attacks, Added to CISA KEVThe Hacker News · Sep 25, 2026
- Critical WSO2 Vulnerability Allow Hackers to Gain Full Admin AccessCyber Security News · Sep 16, 2026
- Enterprises Warned of Attacks Exploiting WSO2 VulnerabilitySecurityWeek · Sep 16, 2026
- Active Exploitation Attempts Target WSO2 API Manager JWT Bypass With Forged Admin TokensThe Hacker News · Sep 16, 2026
- CISA Adds Two Known Exploited Vulnerabilities to CatalogCISA Alerts